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Full-Text Articles in Engineering
Performance Of Ballast Influenced By Deformation And Degradation: Laboratory Testing And Numerical Modeling, Buddhima Indraratna, Ngoc Trung Ngo, Cholachat Rujikiatkamjorn
Performance Of Ballast Influenced By Deformation And Degradation: Laboratory Testing And Numerical Modeling, Buddhima Indraratna, Ngoc Trung Ngo, Cholachat Rujikiatkamjorn
Faculty of Engineering and Information Sciences - Papers: Part B
This paper presents a study on the deformation and degradation responses of railway ballast using large-scale laboratory testing and computational modeling approaches. A series of large-scale triaxial tests were carried out to investigate the ballast breakage responses under cyclic train loading subjected to varying frequencies, f=10-40 Hz. The role of recycled rubber energy-absorbing mats (REAMs) on reducing ballast breakage was also examined. Laboratory test results show that the ballast experiences significant degradation (breakage) and deformation, while the inclusion of REAMs can reduce the ballast breakage up to about 35%. Numerical modeling using the coupled discrete-continuum approach [coupled discrete-element method-finite-difference method …
Power Loss And Thermal Impedance Modeling Of Multilevel Power Converter With Discontinuous Modulation, Md Mazharul Islam, Md. Ashib Rahman, Md Rabiul Islam
Power Loss And Thermal Impedance Modeling Of Multilevel Power Converter With Discontinuous Modulation, Md Mazharul Islam, Md. Ashib Rahman, Md Rabiul Islam
Faculty of Engineering and Information Sciences - Papers: Part B
The hard switching operation of the insulated gate bipolar transistor (IGBT)-based multilevel converters (MLCs) in the transformer less direct integration of renewable power plants produces a considerable amount of switching and conduction power loss. This eventually causes higher junction temperature and lower thermal stability. The third harmonic sixty-degree bus-clamped pulse width modulation (BCPWM) technique demonstrates reduced switching losses and better harmonic spectra. In this paper, an analytical model for calculating the average and the rms currents for the hard switching operation of IGBTs and antiparallel diodes (APDs) is proposed. Furthermore, to calculate the device turn-on and turn-off losses, a discrete …
Experimental Investigation And Modeling Of The Transformation Of Illicit Drugs In A Pilot-Scale Sewer System, Jiaying Li, Jianfa Gao, Phong K. Thai, Adam Shypanski, Ludwika Nieradzik, Jochen F. Mueller, Zhiguo Yuan, Guangming Jiang
Experimental Investigation And Modeling Of The Transformation Of Illicit Drugs In A Pilot-Scale Sewer System, Jiaying Li, Jianfa Gao, Phong K. Thai, Adam Shypanski, Ludwika Nieradzik, Jochen F. Mueller, Zhiguo Yuan, Guangming Jiang
Faculty of Engineering and Information Sciences - Papers: Part B
In-sewer stability of illicit drug biomarkers has been evaluated by several reactor-based studies, but less has beendone in sewer pipes. Experiments conducted in sewer pipes have advantages over lab-scale reactors in providing more realisticbiomarker stability due to theflow and biological dynamics. This study assessed the transportation and transformation of sevenillicit drug biomarker compounds in a pilot-scale rising main and a gravity sewer pipe. Biomarkers presented diverse stabilitypatterns in the pilot sewers, based on which a drug transformation model was calibrated. This model was subsequently validatedusing transformation data sets from the literature, aiming to demonstrate the predictability of the pilot-based transformationcoefficients …
Modeling And Identification Of A Realistic Spiking Neural Network And Musculoskeletal Model Of The Human Arm, And An Application To The Stretch Reflex, Manish Sreenivasa, Ko Ayusawa, Yoshihiko Nakamura
Modeling And Identification Of A Realistic Spiking Neural Network And Musculoskeletal Model Of The Human Arm, And An Application To The Stretch Reflex, Manish Sreenivasa, Ko Ayusawa, Yoshihiko Nakamura
Faculty of Engineering and Information Sciences - Papers: Part B
This study develops a multi-level neuromuscular model consisting of topological pools of spiking motor, sensory and interneurons controlling a bi-muscular model of the human arm. The spiking output of motor neuron pools were used to drive muscle actions and skeletal movement via neuromuscular junctions. Feedback information from muscle spindles were relayed via monosynaptic excitatory and disynaptic inhibitory connections, to simulate spinal afferent pathways. Subject-specific model parameters were identified from human experiments by using inverse dynamics computations and optimization methods. The identified neuromuscular model was used to simulate the biceps stretch reflex and the results were compared to an independent dataset. …